增加可用优惠券数量

src/main/resources/mapper/TbSystemCouponsMapper.xml

@@ -24,6 +24,9 @@
     <select id="selectAll" resultType="com.chaozhanggui.system.cashierservice.entity.TbSystemCoupons">
       select * from tb_system_coupons where status = '0' and name = #{type}
     </select>
+    <select id="selectByAmount" resultType="java.lang.Integer" parameterType="java.math.BigDecimal">
+      select ifnull(count(*),0) from tb_system_coupons where status = '0' and coupons_amount >= #{orderNum}
+    </select>
     <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer">
     delete from tb_system_coupons
     where id = #{id,jdbcType=INTEGER}